240 likes | 335 Views
What is a Mineral?. Properties:. S olid Cannot be a liquid or a gas N aturally Occurring Found in nature, not man-made I norganic Is not alive and never was, non-living F ixed composition
E N D
Properties: • Solid • Cannot be a liquid or a gas • Naturally Occurring • Found in nature, not man-made • Inorganic • Is not alive and never was, non-living • Fixed composition • Has a chemical formula, most are formed from compounds of two or more elements, some minerals consist of one element ex. Au • Crystal Form • A definite structure in which atoms are arranged
Definition: A mineral is a naturally formed, inorganic solid that has a definite crystalline structure.
Questions to ask yourself when determining if an item is a mineral or not: • Is it non-living material? • Is it a solid? • Is it formed in nature? • Does it have a crystalline structure? The next few slides show an assortment of items. As a group, categorize the items as either: Minerals or Non-Minerals.
And the answers are… • Minerals • Gold • Topaz • Quartz • Talc • Iceberg* • Diamonds • Non-Minerals • Wood - once living • Fossils – once living • Bone - living material • Granite - intrusive igneous rock • Pearls – made by oysters • Coal - Sedimentary rock • Rock Salt – Sedimentary rock According to IMA– ice is listed as a mineral. Why?
Two Groups of Minerals • Silicates • Contains Silicon (Si) and Oxygen (O) • 90% of Earth’s crust • Combine with elements such as Al, Fe, Mg, and K • Nonsilicates • Do not contain combinations of Si and O • May contain C, O, F, S • Classes of Nonsilicates • Native Elements: Au, Cu, Ag • Oxides : Al or Fe combine with O • Carbonates: C + O • Sulfates: S + O • Halides: F, Cl, I, or Br combine with Na, K, or Ca • Sulfides: Pb, Fe, Ni, combine with S
Identifying Minerals • Color – the same mineral can come in a variety of colors, not reliable
Luster – the way in which a mineral reflects light • Metallic - opaque and reflective, like metal • Submetallic - to nearly opaque and reflect well • Nonmetallic - not looking like a metal at all • Vitreous - glassy • Silky - fibrous • Resinous – yellow, dark orange, brown • Waxy • Pearly – like inside a mollusk • Earthy – dull, looks like dirt or clay
Streak – the color of the mineral in a powdered form • Cleavage – when minerals break along a smooth, flat surface • Fracture – when minerals break unevenly along a curved or irregularsurface
Hardness – a minerals resistance to being scratched • Moh’sScale of Hardness 1 - 10
Density – how much matter is in a given amount of space • Special Properties • Fluorescence – glow under ultraviolet light • Chemical Reaction – fizzes with acid test • Optical Properties – double image formed • Magnetism – magnetic, attract iron • Taste – salty • Radioactivity – radium or uranium contained